package bing.utils
{
	import flash.system.Capabilities;
	
	public class Guid
	{
		private static var counter:Number=0;
		
		public static function create():String
		{
			var dt:Date=new Date();
			var id1:Number=dt.getTime();
			var id2:Number=Math.random() * Number.MAX_VALUE;
			var id3:String=flash.system.Capabilities.serverString;// System.capabilities.serverString;
			return calculate(id1 + id3 + id2 + counter++).toUpperCase();
		}
		private static function calculate(src:String):String
		{
			return hex_sha1(src);
		}

		private static function hex_sha1(src:String):String
		{
			return binb2hex(core_sha1(str2binb(src), src.length * 8));
		}

		private static function core_sha1(x:Array, len:Number):Array
		{
			x[len >> 5]|=0x80 << (24 - len % 32);
			x[((len + 64 >> 9) << 4) + 15]=len;
			var w:Array=new Array(80), a:Number=1732584193;
			var b:Number=-271733879, c:Number=-1732584194;
			var d:Number=271733878, e:Number=-1009589776;
			for (var i:Number=0; i < x.length; i+=16)
			{
				var olda:Number=a, oldb:Number=b;
				var oldc:Number=c, oldd:Number=d, olde:Number=e;
				for (var j:Number=0; j < 80; j++)
				{
					if (j < 16)
						w[j]=x[i + j];
					else
						w[j]=rol(w[j - 3] ^ w[j - 8] ^ w[j - 14] ^ w[j - 16], 1);
					var t:Number=safe_add(safe_add(rol(a, 5), sha1_ft(j, b, c, d)), safe_add(safe_add(e, w[j]), sha1_kt(j)));
					e=d;
					d=c;
					c=rol(b, 30);
					b=a;
					a=t;
				}
				a=safe_add(a, olda);
				b=safe_add(b, oldb);
				c=safe_add(c, oldc);
				d=safe_add(d, oldd);
				e=safe_add(e, olde);
			}
			return new Array(a, b, c, d, e);
		}

		private static function sha1_ft(t:Number, b:Number, c:Number, d:Number):Number
		{
			if (t < 20)
				return (b & c) | ((~b) & d);
			if (t < 40)
				return b ^ c ^ d;
			if (t < 60)
				return (b & c) | (b & d) | (c & d);
			return b ^ c ^ d;
		}

		private static function sha1_kt(t:Number):Number
		{
			return (t < 20) ? 1518500249 : (t < 40) ? 1859775393 : (t < 60) ? -1894007588 : -899497514;
		}

		private static function safe_add(x:Number, y:Number):Number
		{
			var lsw:Number=(x & 0xFFFF) + (y & 0xFFFF);
			var msw:Number=(x >> 16) + (y >> 16) + (lsw >> 16);
			return (msw << 16) | (lsw & 0xFFFF);
		}

		private static function rol(num:Number, cnt:Number):Number
		{
			return (num << cnt) | (num >>> (32 - cnt));
		}

		private static function str2binb(str:String):Array
		{
			var bin:Array=new Array();
			var mask:Number=(1 << 8) - 1;
			for (var i:Number=0; i < str.length * 8; i+=8)
			{
				bin[i >> 5]|=(str.charCodeAt(i / 8) & mask) << (24 - i % 32);
			}
			return bin;
		}

		private static function binb2hex(binarray:Array):String
		{
			var str:String=new String("");
			var tab:String=new String("0123456789abcdef");
			for (var i:Number=0; i < binarray.length * 4; i++)
			{
				str+=tab.charAt((binarray[i >> 2] >> ((3 - i % 4) * 8 + 4)) & 0xF) + tab.charAt((binarray[i >> 2] >> ((3 - i % 4) * 8)) & 0xF);
			}
			return str;
		}
	}
}